ieee802154: mac802154: handle the reserved dest mode by dropping the packet

If received frame contains the reserved destination address mode. The
frame should be dropped and free the skb.
Signed-off-by: NMartin Townsend <martin.townsend@xsilon.com>
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

net/mac802154/wpan.c

@@ -462,7 +462,10 @@ mac802154_subif_frame(struct mac802154_sub_if_data *sdata, struct sk_buff *skb,
 			skb->pkt_type = PACKET_OTHERHOST;
 		break;
 	default:
-		break;
+		spin_unlock_bh(&sdata->mib_lock);
+		pr_debug("invalid dest mode\n");
+		kfree_skb(skb);
+		return NET_RX_DROP;
 	}
 
 	spin_unlock_bh(&sdata->mib_lock);